[tor-bugs] #7912 [Tor]: Cells that don't get inserted into cell queues can clog connection flushing

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#7912: Cells that don't get inserted into cell queues can clog connection flushing
------------------------------------+---------------------------------------
 Reporter:  asn                     |          Owner:                    
     Type:  defect                  |         Status:  needs_review      
 Priority:  major                   |      Milestone:  Tor: 0.2.4.x-final
Component:  Tor                     |        Version:                    
 Keywords:  tor-relay 023-backport  |         Parent:                    
   Points:                          |   Actualpoints:                    
------------------------------------+---------------------------------------

Comment(by andrea):

 Update on testing: after 6.5 hours, a middle relay configured with 80
 kbyte/sec average, 120 kbyte/sec burst has the following heartbeat log
 entry:

 Jun 13 05:20:35.000 [notice] Heartbeat: Tor's uptime is 6:30 hours, with 7
 circuits open. I've sent 435.56 MB and received 431.80 MB.

 The destroy statistics are:

 {{{
 andrea at tor-dev:~/tor-test/bug7912 [39]$ grep -Hne 'notify_xmit_destroy'
 debug.log | wc -l
 681
 andrea at tor-dev:~/tor-test/bug7912 [40]$ grep -Hne 'notify_xmit_destroy'
 debug.log | tail
 debug.log:8219257:Jun 13 05:19:04.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0xee50e0 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8219663:Jun 13 05:19:10.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0x1816c50 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8219896:Jun 13 05:19:20.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0x18313c0 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8220856:Jun 13 05:20:09.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0xfe3880 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8221071:Jun 13 05:20:25.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0x198b590 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8221100:Jun 13 05:20:26.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0x197d450 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8221874:Jun 13 05:21:45.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0x1892230 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8222328:Jun 13 05:22:06.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0x1890750 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8222848:Jun 13 05:22:24.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0x1a05ef0 sent a destroy, cmux
 counter is now 0, global counter is now 0
 debug.log:8223105:Jun 13 05:22:28.000 [debug]
 circuitmux_notify_xmit_destroy(): Cmux at 0x1a10f50 sent a destroy, cmux
 counter is now 0, global counter is now 0
 }}}

 Looks like it's working just fine.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7912#comment:35>
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